package com.hmdp.utils;

import cn.hutool.core.lang.UUID;
import com.hmdp.service.ILock;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;

import java.util.Collections;
import java.util.concurrent.TimeUnit;

public class SimpleRedisLock implements ILock {

    public static final String ID_PREFIX = UUID.randomUUID().toString(true)+"-";
    public static final DefaultRedisScript<Long> UNLOCK_SCRIPT;
    static {
        UNLOCK_SCRIPT = new DefaultRedisScript<>();
        UNLOCK_SCRIPT.setLocation(new ClassPathResource("unlock.lua"));
        UNLOCK_SCRIPT.setResultType(Long.class);
    }

    String name;
    StringRedisTemplate stringRedisTemplate;


    public SimpleRedisLock(String name, StringRedisTemplate stringRedisTemplate) {
        this.name = name;
        this.stringRedisTemplate = stringRedisTemplate;
    }

    public static final String KEY_PREFIX = "LOCK";


    @Override
    public boolean tryLock(Long timeoutSec) {
        //get thread id
        String threadId = ID_PREFIX+ Thread.currentThread().getId();
        Boolean success = stringRedisTemplate.opsForValue().
                setIfAbsent(KEY_PREFIX + name, threadId + "", timeoutSec, TimeUnit.SECONDS);
        return Boolean.TRUE.equals(success);

    }

    @Override
    public void unlock() {
        //get thread id
//        String threadId = ID_PREFIX+ Thread.currentThread().getId();
//        String id = stringRedisTemplate.opsForValue().get(KEY_PREFIX+name);
//        if (threadId.equals(id)){
//            stringRedisTemplate.delete(KEY_PREFIX + name);
//            return true;
//        }
//        return false;
        //调用LUA脚本
        stringRedisTemplate.execute(
                UNLOCK_SCRIPT,
                Collections.singletonList(KEY_PREFIX+name),
                ID_PREFIX+Thread.currentThread().getId());
    }
}
